Kay MA-4 20 HP Phasemaster Rotary Type Phase Converter
Highlights:
- Maximum motor horsepower 20 HP Horsepower - A comparable way of measuring the amount of power output of a motor or engine (1 horsepower = about 746 watts)
- Maximum total horse power 60 HP
- L 21, W 21, H 28, Wt. 487lbs
- Power 1ph Single Phase motors from a 3ph Three Phase power supply
- Other sizes available CALL >>>>
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Is Rotary or Static for You?
Rotary 3-phase converters are the most flexible and reliable type of phase converter. They produce true 3-phase power to run any type of load or combination of motors. For this reason, Kay Industries recommends rotary phase converters for most applications requiring a phase converter.
Static 3-phase converters do not produce true 3-phase power. In fact, static phase converters are little more than electric rope starters. Unlike a rotary phase converter, static phase converters cannot balance the load between the three legs after the motor has started. As a result, static 3-phase converters never allow your motor to develop full horsepower. Static phase converters are thus suited only for small-horsepower, single-motor applications. In addtion, they cannot be used for heaters or rectifier loads.
Consider a static 3-phase converter only if your application:
- Starts quickly
- Starts infrequently (less than four times in an hour)
- Runs at less than 70% of its nameplate horsepower
Full nameplate output for extended periods is only possible with a rotary phase converter. If your application requires a long acceleration time, you'll need a rotary phase converter.
Check the table below for more comparisons between rotary and static phase converters.
| Feature: | Rotary | Static |
| Single motor loads | Yes | Yes |
| Multiple motor load | Yes | No |
| Rectifier & heat loads | Yes | No |
| Load output | 100% of NP rating | 60-80% of NP rating |
| Limits on load starts | None | 6 per hour |
| Long term reliability | Very High | Adequate |
| Variable load range | High | Limited |
| Relative cost | High | Low |
| Efficiency at full load | >99% | 95% |
| HP range | 1 - 500 | 1/2 - 20 |
| Maintenance Requirements | None | Some but minimal |
If a static phase converter is right for your application, the MiniPhase Static 3-Phase Converter is the best you can buy, it is built with the same attention to engineering quality and comes with the same service and documentation that has made Phasemaster Rotary Converters the industry leader.




